This grant represents in effect a competitive renewal for 2 grants, HL-18918 (Characterization of Lung Elastin) and HL-15965 (Elastin metabolism in Atherosclerosis). The specific aims of both grants have been combined and are: 1) to isolate and characterize elastin fiber precursors from lung and aorta sources, 2) quantify changes in elastin synthesis and accumulation (deposition) during lund and aorta development, 3) identify factors that influence elastin metabolism, and 4) identify or clarify post-translation steps important to elastic fiber deposition. The methodologies will involve whole animal, tissue culture, and cell-free translation studies dealing eith elastin biosynthesis in relationship to development, diet, endocrine, and disease model relationships. It is the hope that the findings will have application to concepts inportant to a better understanding of elastin's role in developmental emphysema, other forms of chronic obstructive lung disease and vessel wall development in health and disease.